H.M. Divekar

New experimental model for the evaluation of adaptogenic products

A new animal model for evaluating improvement in physical work performance and endurance in an adverse environment is described. In this model, rats in restraint were exposed to 5 degrees C at 480 mmHg atmospheric pressure. Results were compared to an animal forced to swim in water at 23 degrees C. In both the models, colonic temperature (Tr) of the rats was continually monitored during exposure to adverse environment and during recovery at 32 degrees C and normal atmospheric pressure. The time and pattern for Tr fall to 23 degrees C and its recovery to 37 degrees C were used as measures of endurance. The cold-hypoxia-restraint model was found to provide more precise results compared with the cold-swimming model. Panax ginseng root and Ginkgo biloba leaf extracts were compared for their positive endurance-promoting properties using both models.

Enhanced thermogenesis in rats byPanax ginseng, multivitamins and minerals

Substances which enhance endurance for physical and mental work and increase non-specific resistance to stress during a prolonged stay in physiologically adverse habitats are called ‘adaptogens’.Panax ginseng is well known for its anti-stress and adaptogenic properties. In the present study, adaptogenic activity by the intake of a herbo-vitamin-mineral preparation (HVMP) containingP. ginseng and multivitamin-mineral preparation (MVMP) was evaluated using the cold-hypoxia-restrained (C-H-R) animal model. The aim was to determine whether the cold tolerance and recovery from acute hypothermia mediated byP. ginseng was modified by simultaneous intake of additional vitamins and minerals. Results suggest that the adaptogenic effect of HVMP was more or less the sum total of its two componentsP. ginseng and MVMP. In HVMP,P. ginseng was found to be effective for developing resistance to cooling and MVMP helped in stimulating faster recovery from acute hypothermia.

Anti-stress and Adaptogenic Activity of l-Arginine Supplementation

In the present study, oral supplementation of l-arginine in rats was evaluated for its anti-stress and adaptogenic activity using the cold (5°C)–hypoxia (428 mmHg)–restraint (C-H-R) animal model. A dose-dependent study of l-arginine was carried out at doses of 12.5, 25.0, 50.0, 100.0, 200.0 and 500.0 mg/kg body weight, administered orally 30 min prior to C-H-R exposure. The time taken by the rat to attain a rectal temperature of 23°C (Trec 23°C) during C-H-R exposure and its recovery to Trec 37°C at normal atmospheric pressure and 32 ± 1°C were used as biomarkers of anti-stress and adaptogenic activity. Biochemical parameters related to lipid peroxidation, anti-oxidants, cell membrane permeability, nitric oxide and stress, with and without administration of the least effective l-arginine dose, were measured in rats on attaining Trec 23°C and Trec 37°C. The least effective adaptogenic dose of l-arginine was 100.0 mg/kg body weight. The C-H-R exposure of control rats, on attaining Trec 23°C, resulted in a significant increase in plasma malondialdehyde (MDA), blood lactate dehydrogenase (LDH) and a decrease in blood catalase (CAT) and plasma testosterone levels. On recovery (Trec 37°C) of control rats, there was a further decrease in CAT and plasma testosterone, and an increase in LDH. l-Arginine supplementation resulted in a significant decrease in plasma MDA, an increase in blood superoxide dismutase (SOD), CAT levels maintained at control values and a lower increase in LDH compared with controls (45.3 versus 58.5% and 21.5 versus 105.2%) on attaining Trec 23°C during C-H-R exposure and on recovery to Trec 37°C. The results suggested that l-arginine possesses potent anti-stress activity during C-H-R exposure and recovery from C-H-R-induced hypothermia.

Experimental Evaluation of a Composite Indian Herbal Preparation II (CIHPII) as an Adaptogen and its Mechanism of Action

AbstractCIHP II, an Ayurvedic combination of several plant ingredients and minerals, was tested for its adaptogenic action. CIHP II had a strong adaptogenic action in single, multiple, and prolonged dose schedules. It had a cumulative adaptogenic property. CIHP II intake resulted in an improved maintenance of blood glucose levels at the end of exhaustive swimming exercises with little difference in blood lactic acid as compared with control rats without CIHP II intake. This suggested conservation of glucose utilisation. CIHP II was found to potentiate the oxygen delivery system by increasing red cell 2,3 Diphosphoglyceric acid (2,3-DPG) levels on exposure to hypobaric hypoxia. It improved cellular membrane permeability, as the release of creatine phosphokinase in circulation during hypobaric hypoxia was restricted on CIHP II intake. However, several tissue metabolite concentrations were not altered during the resting state. The CIHP II appeared to induce a state of non-specific increased resistance (SNIR)...

Effect of 1-Oxo-5β, 6β-Epoxy-Witha-2-Ene-27-Ethoxy-Olide Isolated from the Roots of Withania somnifera on Stress Indices in Wistar Rats

OBJECTIVE Isolation of biologically active fractions and compounds from the roots of Withania somnifera, a plant used extensively as a constituent of rasayana, in Ayurveda and to test their adaptogenic activity on stress indices using the cold-hypoxia-restraint (C-H-R) model. DESIGN Bioactivity-guided fractionation of an aqueous extract of the roots of Withania somnifera led to the isolation of a new species of withanolide 1-oxo-5beta, 6beta-epoxy-witha-2-ene-27-ethoxy-olide. Structure elucidation, was carried out using proton nuclear magnetic resonance, infrared (IR), ultraviolet (UV), and mass spectroscopic analysis. Stress-related indices were evaluated, namely serum creatine phosphokinase (CPK) activity, serum lactate dehydrogenase (LDH) activity, serum corticosterone levels, and serum lipid peroxidation (LPO) levels. RESULTS There was a significant decrease in a serum CPK, LDH, and LPO levels in animals pretreated with (1) fraction-I (20 mg/kg body weight), (2) 1-oxo-5beta, 6beta-epoxy-witha-2-ene-27-ethoxy-olide (2.5 mg/kg body weight) in comparison to control when subjected to C-H-R stress. CONCLUSIONS The results show that the a new species of withanolide, 1-oxo-5beta, 6beta-epoxy-witha-2-ene-27-ethoxy-olide (compound-1) could prove to be an effective agent to counteract C-H-R stress.

Antistress and Adaptogenic Activity of Lecithin Supplementation

OBJECTIVE Investigation of lecithin administration in rats for its antistress and adaptogenic activity. DESIGN Lecithin was administered orally (1 mg/g body weight) to rats 0.5 hour, 1.5 hours, 3.0 hours, and 6.0 hours prior to cold (5 degrees C)-hypoxia (428 mm Hg)-restraint (C-H-R) exposure and serum choline estimation. The rectal temperature (T(rec)) of the rats was monitored during the exposure and the recovery periods. The time for decrease of T(rec) to 23 degrees C and its recovery to 37 degrees C were used as indices of antistress and adaptogenic activity. RESULTS Lecithin administration 3-6 hours prior to C-H-R exposure was found to have significant adaptogenic activity that correlated with increased serum choline levels. Lecithin administration prior to C-H-R exposure increased the stress tolerance of the rats by delaying the time for decrease of T(rec) to 23 degrees C during C-H-R exposure. It also helped shorten poststress recovery as observed by decreased time to attain T(rec) of 37 degrees C from C-H-R-induced hypothermia (T(rec), 23 degrees C). CONCLUSIONS The results suggested that lecithin supplementation acted as an antistress and adaptogenic functional food. It improved resistance during C-H-R exposure and enhanced recovery from hypothermia.

Ninety days of repeated gavage administration of Rhodiola imbricata extract in rats.

Rhodiola imbricata is a high‐altitude plant, possesses adaptogenic, immunomodulatory, anti‐oxidant and cytoprotective activity, and is widely used in traditional medicine. The present study was designed to ascertain the safety of aqueous extract of R. imbricata root when administered by gavage to rats for 90 days. Four groups of animals, each consisting of 15 males and 15 females, were administered 0, 100, 250 or 500 mg kg−1 extract, in a single dose per day. The experimental rats when administered 100 mg kg−1 of extract did not show any significant change in their body weight gain, organ/body weight ratio, or histological, hematological and biochemical variables studied. However, at higher doses of 250 and 500 mg kg−1 extract, an increase in the body weight of rats of both the sexes was apparent without any change in their organ/body weight ratio. Furthermore, a noteworthy increase in plasma glucose and protein levels was recorded at both the higher doses, which were restored to normal after a 2‐week withdrawal of treatment. Based on the findings of this study, the no observed effect level was 100 mg kg−1 body weight per day of aqueous root extract of R. imbricata in rats administered subchronically. Copyright